Intra-cavity coherent combining of DBR lasers on an InP generic foundry platform

We report an intra-cavity coherent combining of two distributed Bragg reflector (DBR) lasers with a combining efficiency of ∼84% on an InP generic foundry platform. The on-chip power of the intra-cavity combined DBR lasers is ∼9.5 mW at the injection current of 42 mA in both gain sections simultaneously. The combined DBR laser operates in a single-mode regime with a side-mode suppression ratio of 38 dB. This monolithic approach paves the way toward high-power and compact lasers, which is useful in scaling integrated photonic technologies.